St Catherine’s College, Ainworth Centre, Oxford

The new Ainsworth Graduate Centre is a striking circular design yet one that sits harmoniously in a location steeped in history. The building resides on the site of the original Grade I listed campus designed by renowned architect Arne Jacobsen.

Built between 1960 and 1964, Jacobsen designed the college’s main campus in its entirety. Since Jacobsen’s death in 1971 additional buildings have been delivered by the Danish architect’s assistant, Knud Holscher, and Stirling Prize-winning RIBA past president Stephen Hodder. Architects Purcell designed the new Graduate Centre as a continuation of the second phase of Hodder’s development by following his typology as sensitively as possible.

Proteus HR TECU bronze cladding panels were specified for the cylindrical three-storey hub, which features a seminar room and common room, as a reference to Jacobsen’s use of the material on previous projects at the college, synchronising old with new.

Proteus HR is a modular rainscreen system that offers a smooth façade with recessed joints. The panels have a lightweight aluminium honeycomb core structurally bonded between two thin gauges of metal. The lightweight nature of this rainscreen system minimises weight loadings on the underlying structure whilst achieving strength and rigidity.

The panels are fixed onto a unique system of aluminium carriers and ancillary components, which were designed and manufactured by Proteus Facades. Proteus fabricated the structural element of the fixing system so that it physically curves around the building. Installers Norman & Underwood then secured the flat panels to create a faceted façade that, when viewed from afar gives the perception that it is curved around a tight radius.

Proteus Facades also fabricated three varieties of TECU bronze fins for external use on glazed sections. Shorter fins were secured with a modified vertical aluminium extrusion cloaked with TECU bronze and secured with stainless steel brackets. Each one is fixed off the curtain wall system, with the TECU bronze capping designed bespoke to achieve the maximum depth from the glazing line to create a more striking aesthetic.

Deeper, vertical TECU Bronze fins are secured to a bespoke structural frame up to 450mm off the cladding line, which compartmentalises the façade. The vertical fins frame the structural bay and are fixed off curtain walling, spigoted into the ground and bracketed at the head. The internal aluminium carcass was secured with structural brackets back to the curtain wall and plated at join positions with discrete fixings.

Horizontal beams on the top of the upper level were fabricated in a curve and fixed to a bespoke aluminium structure, then cloaked with the TECU Bronze material from Proteus. Norman & Underwood secured the beams with structural gusseted brackets fixed back to the primary structure. All three types of fins went through a double-marquette process, where principal and secondary designs were presented to the architects and client for review before manufacture.

As well as a reference to the original campus buildings, the bronze finish of the panels and fins was specified to contrast in tone and glossiness with stainless steel panels, also manufactured by Proteus Facades, which feature on existing and the newly developed student accommodation blocks adjacent to the centre.

In the early 1990s and 2000s Hodder added three accommodation blocks to the site, housing a total of 54 rooms. The facades on these buildings feature Proteus HR Stainless Steel cladding panels, manufactured by Proteus Façades several decades ago. This material was originally chosen as the smooth finish of the stainless steel stands out against the coarse finish of the concrete structure creating a textured facade.

Like the Graduate Centre, the newest student accommodation pavilions are a continuation of Hodder’s development, adding 78 large spacious en-suite rooms connected by glazed stairwells. The façades of the new buildings imitates those constructed by Hodder, and so Proteus Facades was appointed to fabricate exact replicas of the original Stainless Steel panels they manufactured some twenty years previous for the new development, whilst using more modern methods of construction.

The stainless steel panels sit inboard of the building’s concrete frame with a standard pattern of two panels adjacent to large rectangular windows on each of the rooms. The Proteus HR rainscreen panels were supplied pre-finished with a 240S brushed polished finish.

The aluminium carrier system used is fully adjustable on all axis, allowing exacting sightlines to be maintained across the façade. This enables the façade at St Catherine’s college to make the most of linear shadow lines between the Proteus HR panels and concrete structure.

24 King William Street, London

The £23 million renovation of the 80,730 ft² building, located on the northern approach to London Bridge, was designed by Ben Adams Architects and includes the addition of two new storeys.

An elegant reception area comprises of a double height entrance hall leading into a lift lobby, finished with Portland stone floors and feature walls in marble and leather, with brass accents throughout. To reflect the style within, striking perforated Proteus SC TECU Brass panels and bespoke vertical fins and trim flashings, with an Artisan hand applied patinated finish were specified for the ground level, street facing elevations.

The fins at 24 King William Street are designed around a rigid bespoke aluminium extrusion that connects to the curtain wall glazing system. The outer TECU Brass element of the fins are profiled in shape and taper across the length to generate an angled effect – the fins increasingly extend outwards as they ascend – whilst the connection of the material to the extrusion and the window frame remains constant.

The internal aluminium structure of the fins provides the necessary support and structural connection back to the curtain walling. This also created a depth at the rear, hiding the curtain wall system from plain view and giving passers by the perception that the fins float in front of the glazing system.

The combination of thin gauge brass material and internal aluminium support framework ensured that this element of the façade met budgetary requirements. Proteus’s in-house expertise also overcame the difficult folding requirements of the TECU Brass fin profile, which were towards the limits of current bending technology.

The fins are complemented by Proteus SC perforated panels, which are fixed over insulated spandrel panels within the curtain wall system. These panels hide the ventilation elements of the curtain wall and blend the fins and curtain wall system together. The panels were finished with the Artisan patination effect which is created by applying a fine linear /orbital grain brush effect to the face of the material before having the chemical application and sealing. The panels will gradually weather over time and continue to embellish the already highly desirable warm ochre hues of the Artisan hand patinated finish.

The TECU Brass is developed by blending copper and zinc, which creates an extremely tough, robust façade and then applying a patinated finish that adds texture and contrast, giving a richly aged aesthetic. This rich diversity of the copper-alloy material allows unparalleled variety and high-quality aesthetics, complementing the natural stone and brass tones of the lobby.

A touch of zinc

The rear elevation of the nine-storey building near Monument station features an equally impressive façade complete with Proteus HR Graphite Grey Rheinzinc rainscreen panels. This zinc material then wraps up and over, forming a curved zinc roofing system which blends vertical and horizontal elevations into one. The material is gaining favour with architects and developers as it provides a long, maintenance-free life and offers adaptability to various design styles ranging from traditional to modern.

Once dominated by rambling plant rooms, the interior of the zinc roof is now home to state of the art offices overlooking the City and the River Thames. A limestone façade featured on the front of the building connects to the roof through Proteus’ perforated flat sheets in a United Anodisers UnAtex bespoke finish.

These United Anodisers UnAtex panels are also integrated within the windows on the top two floors, and then flow up and onto the roof generating the patterned effect, while making is look like the façade and roof become one element.

Together this juxtaposition of materials has helped to bring an outdated and under-utilised 1980’s office building back into use; transforming it into a modern, aesthetically pleasing structure that stands out amongst many others in a prominent and sought-after location within the Capital.

Redeveloped to a Grade A specification, the building includes a tranquil new garden coupled with new retail spaces at ground floor level.

Molecular Sciences Research Hub, Imperial College

The concrete façade, combined with the perforated cladding and triple glazed curtain walling on the Hub fuse together to outwardly portray what this innovative research facilities does on the inside.

Aukett Swanke chose Capisco’s CAP 55 finish for the Proteus SC perforated panels early in the design process because they were looking to complement the flat bare concrete façade and glazed elements.

The CAP 55 effect was hand applied by patination specialist Capisco, which gave the Proteus SC TECU Brass perforated panels an enhanced flow, feel and texture. The appearance of the perforated and patinated panels now changes depending on the level of sunlight and the angle at which they are viewed from. The end result is a strikingly beautifully aesthetic that appears to move and shimmer across the visually flat façade beneath.

The perforated panels seamlessly transition through the entrance glazing to form a striking feature within the atrium entrance. This creates an impressive solar composition, accentuated by spotlights, when visitors cast their eyes upwards.

“The contrast between the concrete, glass and patinated brass couldn’t be more complementary and, with it, pleasing to the eye,” said Elias Niazi, Design Principal at Aukett Swanke. “The visual outcomes on this project have exceeded expectations. The perforated patterns on the brass panels with artistic patinations add a sense of mystery and mirror the innovative research works carried out inside the building.

Elias Niazi, Design Principal explained: “We specified Proteus SC because we liked the wide panels of its TECU Brass perforated system, as well as the company’s ability to work with Capisco on what is a completely bespoke cladding solution.”

Proteus Facades, again working with Capisco to create a matching patinated finish, manufactured the window flashings for the Hub. Initially conceived as a simple window flashing, Proteus had to overcome a real technical challenge – the profile of the window reveal is a narrow box that tapers across the width to make it appear as though the window blends into the concrete.

The maximum depth of the window reveal was too large for traditional manufacturing processes and so a multi piece flashing design was developed which could be stud welded and bolted together. This avoided any distortions that would have resulted from traditional welding processes, whilst creating a bespoke element that could be easily installed on site.

Proteus Facades is able to supply the CAP 55 finish in either Brass or Bronze materials. The TECU Brass Proteus SC perforated panels were developed in conjunction with the supporting composite panel behind. These had a maximum capacity to support the perforated panels, with the required cavity zone, at 750mm centres. Proteus SC perforated hock on panel system was used, set off from the company’s 125x50mm mullion.

The perforated panels encompass a PPC black stainless steel bird mesh, carefully integrated into the back to ensure there was no visual impact to the panel face.

The Molecular Sciences Research Hub encompasses technical and laboratory areas clustered around a full height atrium. The striking new hub forms the centre piece of the Imperial West campus. Laing O’Rourke commenced construction works at the end of 2014 with completion in 2016. The façade was installed by its in-house team, Laing Facades.